[AllowNull] attribute ignored by Resharper

Resharper version = 2020.2.1

Consider the following code from a .Net Core 3.1 console application:

using System;
using System.Diagnostics.CodeAnalysis;

#nullable enable

namespace ConsoleApp1

    class Program
static void Main()
Test test = new Test
SomeProperty = null // R# warning: Possible null assignment.


public sealed class Test
public string SomeProperty
get => _someProperty;

_someProperty =
value != null // R# warning: Expression is always true.
? value
: "default";

string _someProperty = "";

The [AllowNull] attribute tells the compiler that although the SomeProperty getter cannot return null,
the setter can accept null.

The C# compiler is happy with this, and does not issue any warnings or errors.

However, Resharper gives two incorrect warnings, as commented in the code above
("// R# warning: ...").

Is this a problem with Resharper, or have I configured Resharper incorrectly?
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Official comment

Hello Matthew,

Thanks for the report. It is a bug in the code analysis. However, it has already been fixed in 2020.3 branch, and the fix will be available in the first EAP build of ReSharper 2020.3 release cycle.


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Great, thanks for the swift response!


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